Table-desk



D. M. STEVENSON.

Table-Desk.

No 228,570. Patented June 8,1880.

Nrrno STATES PATENT Fries,

TABLE-DESK.

SPECIFICATION forming part of Letters Patent No. 228,570, dated June 8, 1880.

Application filed December 10, 1879.

To all whom it may concern Be it known that I, DONALD M. STEVEN- SON, of Cincinnati, Hamilton county, Ohio, have invented a new and useful Improvement in Table-Desks, of which the following is a full, true, and exact description, reference being had to the accompanying drawings, in which Figure 1 represents a perspective view of my invention, showing the desk closed. Fig. 2 is a corresponding view of same, showing the desk open. Fig. 3 is a side elevation of same, partly in section, showing details of the operative mechanism. Fig. 4 is a partial plan view of same, showing the working parts upon one side.

This invention consists in the combination, in a table-desk, of a sliding top fixed in horizontal ways and rigidly guided in its horizontal movements, a vertically-movable desk ar ranged in the rear portion of the table, and the upper end of which forms a portion of the table-top when in its depressedposition, and mechanism connecting with both said rigidlyguided sliding top and vertically-moving desk, whereby the latter is forcibly and positively adjusted both upward and downward, as will be more fully hereinafter described.

In the drawings herewith, A represents a table-desk to which my invention is applied. B B represent the top of the table, of which the part B is movable horizontally and arranged to slide forward between or upon guides, while the part B forms the top of the vertically-movable desk 0. The desk 0 is made of a size to slide within the inclosureD of the table and be wholly concealed within it when closed down, excepting its top B, which corresponds with and forms part of the table-top. Suitable mechanism is introduced, connecting the desk 0 and sliding table-top B in such manner that the horizontal movement of the table-top causes a simultaneous vertical movement of the desk.

, In the present illustration of my invention the mechanism connecting the sliding top B and desk 0 consists of a bell-crank lever and connecting parts arranged and operating upon each side of the desk 0 as follows: The bellcrank lever E is piyoted at c to the side of the inclosure D, and a spring, S, upon the same pivot is arranged to act in opposition to the weight ofthe desk 0 upon the long arm of the bell-crank. A connecting-rml, g, is pivoted to the end of the bell-crank and to the side of the desk 0 at h. is connected by a pivoted com1ecting-rod,f, with the sliding top B of the table.

These parts being properly proportioned to the movement desired, it will be seen that in shoving the tabletop B inward the desk 0 will be drawn downward, while a contrary movement will elevate it, said movement of the table-top being transmitted to the desk 0 through bell-crank le ers similarly arranged on both sides.

The guiding mechanism is as follows: A bar, J, pivoted at i to the side of the inclosure D and at h to the desk 0, compels the point h of the movable desk (which is near the top) to travel in the arc of a circle whose center is The lower part of the desk 0 is compelled by a guide, I, secured to the side of the inclosure D, upon which a cleat, 75, secured to the side of the desk G, is arranged to slide, to move in the arc of a circle whose center is vertically below and distantfrom the center i.

By this arrangement, when the desk 0 is elevated by drawing out the top B, the lower base of said desk will be forced tightly against the inner edge of the said sliding top, and in forcing in the latter a rapid and guided movement of the desk 0 is obtained.

A pivoted lever may be substituted for the guide is l, or guides maybe used instead of pivoted levers; but I prefer the arrangement shown.

The parts may be held in their ultimate po-' sitions by an ordinary lock and key, as at L.

I am aware that a writing-desk has been constructed with a movable swinging top and a vertically-movin g case containing pigeonholes and drawers, in such manner that when the movable top is lifted and swung out the case will be elevated; but as heretofore made there has been no connection between the movable top and case which will positively move the case both upward and downward; but the case has been permitted to drop into the desk by its own gravity, and, furthermore, as here- The short arm of the bell-crank IOO tofore constructed, the movable top has been hung on slotted links, and when drawn out is caused to be elevated atits rear end; and, further, in order to raise or lower the pigeon-hole case, it is necessary to swing the top on the slotted links both inwardly and outwardly, or upwardly and inwardly, over the top of the pigeon-hole case, which swinging movements are avoided by my rigidly-guided top.

By my invention I provide an elevating and depressing mechanism which has a pivotal connection with the rigidly-guided horizontal sliding top and vertically-moving desk, where by the latter is positively adjusted in both its upward and downward movements, which is very advantageous in producing close joints between the parts and avoiding any danger of the displacement of the sliding desk or list bility to become inoperative.

Having described my invention, I claim 1. The combination, in a table-desk, of a sliding top fixed in horizontal ways and rigidly guided in its horizontal movements, a vertically-movable desk arranged in the rear portion of the table, and the upper end of 25 which forms a portion of the table-top when in its depressed position, and mechanism, such substantially as described, connecting with and attached to both said rigidly-guided sliding top and vertically-moving desk, whereby the latter is forcibly and positively adjusted both upward and downward in the table by the action of the sliding top, as set forth.

2. The bell-crank lever E and connectingrods f and g, combined with the pivoted lever J and guiding devices 70 Z, for preserving the vertical position of the desk 0 in its movement, substantially as specified.

In testimony whereof I have hereunto set my hand this 18th day of September, 1879.

DONALD M. STEVENSON.

WVitnesses:

L. M. HOSEA, O. F. HESSER. 

